Glassware that is repetitively washed in automatic dishwashing machines have a tendency to develop a surface cloudiness that is irreversible. The surface cloudiness is believed to be a type of etching or corrosion of the glass and often manifests itself as an iridescent film that displays rainbow hues when light is reflected off of the surface of the glass. As the glass is repeatedly washed, the surfaced progressively becomes more opaque. This same type of corrosion is seen on other articles that are washed in automatic dishwashing machines including, but not limited to: china, porcelain, and ceramics.
It is believed that the corrosion or etching of the glassware actually relates to two separate phenomena: the first is due to minerals leaching out from the glass composition together with the silicate network hydrolyzing and the second is silicate material depositing and redepositing onto the glass. It is a combination of the two phenomena that can result in the cloudy appearance of glassware that has been repeatedly washed in automatic dishwashers.